Attrition grinder



May 22, 1928. 1,670,714.

J. A. CRAIG ATTRITION' GRINDER Filed Jan. 4, 1924 Patented May 22, 1928.

* UNITED STATES.

PATE T JAMES A. CRAIG, or rnnizsnniia, nnwizonn ATTRITION GRINDER;

' Application filed January 4, 1924. semi No. 684,360,

This invention relates to milling machines or attrition grinders in general and more especially to attrition grinders for use in grinding cracked corn, whole wheat, rye and other flour.

Among the objects ofthe present inven-,

tion it is aimed to provide a vertical attrition grinder in which the grindingplates are tion it isaimed toprovide a hopper or re-;

' being milled. w v

ceiver for the material to be ground having a support thatis'rotated and at the same time screens the material'being received, to separate out any foreign substance that may be injurious to the workingparts of the machine and whichforeign substance it may be desirable to eliminate from the materials With the machines heretofore in use considerable difficulty has been encountered in so disposing and adjusting I the grinding faces, and feeding the material, to be ground so that the wear may be evenly distributed. To this end it is an object of the presentinvention to provide an attrition grinder having grinding faces disposed in horizontal planes and a feeding conduitxcentrally 10 cated to the grinding faces, so, that the material may be received at theinner. centralr, ly located zone of the grinding faces and gradually fed out radially in all directions, so as to insure an even distribution of wear upon the grinding faces. 7 v- Still another object of theinvention is to provide an attrition grinder having grinding facesvdisposed in horizontal planes, from the peripheral edges .of whichthe resulting milled material is discharged, and having an inclined discharging chute to receive the resulting milled material, and direct the same to the discharge. v I

V In the present invention, it is also aimed so to dispose and locate the several active parts to provide acompact machine ut1lizing the available space and parts to the best advantage, with a minimum loss in space, material and energy expended. I Y

' It is afurther object of the invention to produce a machine of maximum etficiency, at a minimum cost of production. 1

These and other features, capabilities an advantages of the invention will appear from the subjoined detail description of one specific embodiment of the invention illustrated 111 the, accompanying drawings, in which,

Fig. -1 is a vertical section of the attrition grinder. a j a In the embodiment illustrated the attrition grinder is shown as comprising three main housing members consist-ingot suitably formed castmgslO, 11, and 12. For convenience of description, the 'castingsll and 12,-

will be referred to 'as'co'nstituting the lower housing portion, and the casting 10 as form-: ing the 'upper housing portion.

The'casting 12 preferably has an annular wall 13, afloor or base port-ion 14:, in which there is a central opening -15,and surrounding the opening 15 an upwardly extending annular journal box forming wall orfixed sleeve 16.; The" casting "12 .isfalso preferably provided-with suitable anchoring means such as the feet 17, extendin downwardly from the lower annular edge t ereof and provided with bolt, openings 18,;to receive bolts for securing the feet, 17, and the casting 12 to the floor orsuitable supporting platform. The upper edge ofthe wall 13 i-sprovided With an annular flange 19 to receive the fiange20-of the casting 11, in which flanges 19 and 20 there are formed registering bolt opening'slto receivethe bolts 21 for-anchoringthecastings ll'and 12'to one another, The, casting 11 as illustrated is provided With an annular wall 22, abase 23 having an enlarged central portion 24:, extending upwardly from the base 23, and throughwliich central portion 24,there is provided a shaft receiving central opening 25 to receive'the shaft 26 which is connected to the motor 27 which is preferably securedto-the base 14.

The "lower fend of the shaft 26vforming as it-does-in the present instance the shaft in the, motor 27 is provided with suitable ball bearings 28, disposed in the upper end of the journal box16. The ball bearings areyieldably supported in place by means of the disk 29, resiliently spaced. from, the disk 30 by the spring 31. The lower disk 30 is further provided with a screw-threaded stud 32, operating in the rotatable sleeve 33 anlit) chore'd to the floor 14. The sleeve 33sprojects below the floor 14 and has secured thereon a suitable hand wheel 34 whereby the lower disk can easily be adjusted in a vertical direction and thereby in turn yieldably adjust the disk 29 supporting the ball bearings28, to provide a yieldable vertical adjusting means for the shaft 26. The enlargement 24 is also preferably provided with the ball bearings 35 and'36 to aid the free running of the shaft 26 in its shaft receiving opening 25. The yieldable vertical adjusting means for the shaft 26 just described forms an important part of the present invention.

- The upper end of the shaft 26 is illustrated as having secured thereto the lower grinding face support 37 which by means of the bolts 38 has secured to the upper face thereof the annular grinding plate 39 to c0- operate with the downwardly facing grinding plate 40 secured to the upper grinding face support 41 which is in turn secured to the sleeve or tubular receiver 42.

The casting 11 has a platform 43 disposed therein and secured to the annular wall 22, in position to receive the milled material from the outer annular edges of the grinding face supports37 'and 41, to direct the same to the discharge opening 45' formed in the wall 22, and communicating with the discharge spout 46 secured to the upper casting 10. For insuring the discharge of the ground material from the platform 43 to the spout 46, there is provided the scraper plate 44 secured to the bottom of the grinding plate support 37 by any suitable means such as the bolts 61. It will be understood that the ground material will be discharged on the outer portion of the platform 43, and that with the centrifugal force transmitted to it by the rot-ative sweep of the scraper arm 44, the ground material when reaching the spout 46 will readily discharge therethrough.

The casting 10 comprises essentially an annular wall 47 which is preferably connected to the casting 11 by the shouldered flanges 48 and 49 formed on the opposing edges of the castings 10 and 11 respectively and secured in position by the bolts 50. The shouldered flanges 48 and 49 as illustrated facilitate the removal of the casting 10 whereby access to the grinding plates 39 and 40 is readily had for the purpose of examination, replacement, repair and the.

like. The shouldered flanges contribute materially to facilitate the proper alining of the castings 10 and 11 andtherewith of the grinding plates 37 and 39, to prevent injury to the several working parts. -The annular wall 47 as an integral part thereof, is provided with the upper enclosure portion 51, having the downwardly extending enlargement 52 provided with a centrally extending sleeve receiving opening 53 to receive the sleeve 42. For aiding the sleeve 42 in its rotation, the enlargement 52 is provided with suitable ball bearings 54 and 55. For rotating the tubular member 42 and therewith the upper grinding face support 41 attached thereto, there is provided the motor 56 preferably secured to the upper portion 51 of the casting 10. The upper end of the tubular member 42 is enlarged-as illustrated to form. a hopper or receiver mouth 57 through which the material to be milled is fed to the milling faces.

The tubularmember 42 is provided with a coarse mesh screen section 58 to separate out foreign substance and the like that may be fed in with the material to be milled, thus 4 to protect the grinding faces if the substance should be in the nature of metal pieces or the like and at the same timeto separate out from the materialto be milled, any Substancesthat are desired to "be eliminated therefrom. Since the tubular memher 42 is rotated and therewith the screen 58 also rotated, the rotative action will contribute materially to expeditethe feedingof the material through such screen, both onv account of. the agitation subjected to the screen by such rotative action-and also on account of the centrifugal force towhich the material so received will be :subjected to spread the materialso received in all directions over the screen. 1 1

As an additional securing or steadying means, the upper portion 51 of the casting 10 is provided with link bolts 59 and '60 which maybe secured to suitable overhead or overhanging supports or the'like, not.

illustrated. I

It is obvious that'various changes and modifications may be made to the details of the construction without departing from the spirit of the invention set forth in the claims hereto appended. I I claim:

1. In combination,

hopper-forming-upper tubular shaft; and

opposed upper. and lower grinding plates, the upper plate havinga central opening and bein mounted on the lower end of'the tubular s aft; and'a rotary screen-disposed across said'shaft. i I

2. In combination, a rotary vertical hopper-forming upper tubular shaft having an enlarged-upper end forming an intermediate shoulder; a transverse rotary screen restinguonsaid shoulder; and a pair of opposed grinding plates, the upper plate having a central opening andmounted on the upper end of said shaft;

3. In combination, a housing including a lower compartment carrying a substantially upright lower shaft, and an upper. compartment remo-vably mounted on the lower compartment. carrying an upper shaft; and opv 110 a rotary vertical posed grinding members mounted on the adjacent ends of said shafts respectively; said upper compartment, upper shaft and upper plate being removable together, said compartments being separable at the grinding plane.

4. In combination, a housing including a lower compartment carrying a vertical lower shaft and an upper compartment removably mounted on the lower compartment at a horizontal meeting plane carrying a hopper-forming upper shaft; said housing beingcut away to form an outlet at said plane; opposed grinding, plates mounted on the adjacent ends of said shafts respectively adjacent to said plane and receiving material therebetween from the upper shaft; and a chute removably secured to the upper compartment for the discharge of material therefrom.

5. In combination, a housing compartment having a lower Wall having a central mounted on the first named compartment and having a downwardly projecting ens largement having an upper bearing bore therein; a vertical shaft rotary in the lower bore; an upper shaft in said upper bore;

ing of heavy metal, and'each having a length and diameter greater than half the diameter of the plates.

'6. In comb1nat1on, a support having a lowermember havlng a lower bearlngbore therein, and a heavy upper enlargement having an upper bearing bore therein; a

'vertical shaft rotary-in the lower bore; a

thrust bearing cooperating with the lower shaft; an upper shaft in said upper bore; a thrust bearing in the upper bore cooperating with the upper shaft; opposed grinding plates mounted on the adjacent ends of said shafts respectively.

JAMES A. CRAIG. 

